How do we help our children with setting up two households?
Involve your children in the process of setting up two households. Mix old and new from their bedrooms. Avoid having the non-primary spouse start new bedrooms from scratch. Work together, and let your children see cooperation.
Avoid becoming territorial with toys and clothing. Such things belong to the children - not to the adults. Invariably, children will unintentionally leave a beloved toy or homework at one household. Work together to straighten out such problems.
This is not a turf war. It's your job to help make your children comfortable in both your home and the home of the other parent. Recognize and understand that the children are going through great changes and they need reassurance from both parents that it's okay to enjoy time in both households. Make sure you provide photos of your spouse in their bedroom at your home. Offer to provide a family picture or picture of yourself for their bedroom in your spouse's home. All of your efforts to help transition the children from a one household family to a two household family will payoff in the resulting adjustment of your children. What more could a parent want?